56 



VEBTEBKATA : MAMMALIA. 



mammals, as the Sloths, Armadillos, Anteaters, etc., are 

 diffident in teeth ; and the Duckbills have horny plates in- 

 stead of teeth. In some kinds of mammals, as in Man, a 



FIG. C3. 



so 



Cranium cf a Dog, under surface. Reduced in size. 



SO, supraoccipital; EzO, exoccipital; BO, basioccipital ; Per, mastoid portion of the 

 periotic; 1y, tympanic bulla; BS. basisphenoid ; 87, zygoiuatic process of the squa- 

 mosal; Ma, malar; AS, alispheuoid; Pt, pterygoid; PS, prespbenoid; Fr, frontal; Vo 

 vomer; P/, palatine; Mz, maxilla; PMz, premaxilla; fm, forameu maguum; oc, occip- 

 ital condyle; pp, paroccipital process; cf, condylar foramen; Jlp, foramen lacerum 

 pnsterius; sw, stylo-mastoid foramen; earn, external auditory meatus; pgf, postgle- 

 uoid foramen; gp, postglenoid process; gf, glenoid fossa; Jim, foramen lace-rum me- 

 dium; fn, foramen ovale; as, posterior opening of alisphenoid canal; fr, foramen ro- 

 tundum and anterior opeuiug of alispheuoid canal ; gf, sphenoidal fissure or forameu 

 acelrum anterius ; np, optic foramen; ppf, posterior palatine foramen ; apf, anterior 

 palatine foramen. 



